Brake means



Oct. 22, 1 v J. c. MCCUNE Er AL BRAKE MEANS Filed June 30, 1959 2 Sheets-Sheet 2 .ATTORNEY Patented Oct. 22, 1940 i PATENT- OFFICE BRAKEMEANS Joseph 0. Home, New, near Pl Edgewood. and George K. I tcairn, Pm, assignors to The WestinghouseAir Brake Company, Wilmerding,

7 I Pas, a corporation of Penney! Application June 30, 1939, Serial No. 282,034 Claims. (0!. 188-153) V This invention relates to brake mechanisms and more particularly to the disk type for use on vehicles such as employed on railroads.

In our pending filed January .31, 1939, there is disclosed a disk brake mechanism particularly adapted, though not limited, for use'on railway. vehicles and one of the main features of this mechanism is that it may be applied to and removed from a wheel 1 to be braked as a unit. By this construction the brake mechanism may be completely assembled as a new or repaired unit in a shop remotefrom the point of use and where desired facilities for such work and competent workmen. are readily,

15 available. Then as a preassembled unit the" brake mechanism may, if desired, be shipped to and stored at. a point of application on the rail- .i'oad until it is desired to apply same to a vehicle, at which time such application may be readily effected by relatively unskilled workmen and with the simplest of tools.

One object of the present invention is to provide a novel disk brake mechanism of the unit type above described. V

The disk brake mechanism disclosed in our above referred to pending application comprises a pile of interleaved, annular rotatable and non-' rotatable friction brake elements and a brake cylinder device arranged atone end of the pile of brake elements and operative by fluid under pressure to urge said elements into frictional interengag ement with each other to efiect braking of the wheel to which the mechanism is secured. The brake elements and'brake cylinder device are carried by a structure which is secured to the vehicle wheel by bolts or the like. This structure is provided with one bearing upon which the brake cylinder device is journaled and supported and also has a radial thrust bearing for engagement by the brake cylinder device to hold it against axial movement for counteracting the thrust thereof against the brake elements A during braking. I

Another object of the invention is to provide a novel, unit disk brake mechanism in which no thrust bearing is required; the various parts of the brake mechanism being so constructed and arranged that the brake elements themselves counteract the thrust of the brake cylinder device. v 7

Other objects and advantages will appear in the following more detailed description of the invention.

In the accompanying drawings, Fig. 1 is a horizontal, sectional view of a railway vehicle application Serial No. 25311 71.

Description of parts In the drawings the brake mechanism embodying the invention is shown associated with a wheel I o the type employed under railway vehicles, for he purpose of illustrating one ap-- plication of the invention. Wheel I is provided 1 with the usual flanged tread portion for engaging a rail 2 of a trackway and has at its centera hub 3 in which there is secured in any desired manner the usual axle l. The novel brake mechanism is preferably secured to the 20 outer face of the wheel I, as will be later brought out in detail, in order to facilitate the application of the mechanism to the wheel and the removal of said mechanism from the wheel.

; The 'novel brake mechanism comprises a sleeve 25 I having at one end an outturned annular flange 8, said sleeve and flange constituting a combined bearing. and support member for the various parts of the brake mechanism to be later described. 30

An annular ring-like disk member 9, having a greater outside diameter than that of the flange 8, is secured against the outer surface of the flange 8 preferably by welding. Mounted against the opposite face of flange 8 is an annular ring- 35 like member "I which comprises an inner, radially extending annular portion 5 for engaging said flange, an outer radially extending annular portion I l and a central cylindrical portion l2 connecting said radial portions, said cylindrical 4o portion being provided to space the radial portion H, which is of the same outside diameter as that of memberS, a predetermi ed distance from said member, as shown in E g: '1 of the drawings.

The ring-like member ID is rigidly secured against the inner-face of the flange 8 in coaxial relation with the ring-like member 9 by a plurality of torque screws l3 extending through suitably aligned openings in the inner peripheral.

equally spaced from each other around the flange 8, and between one or more adjacent pairs of said torque screws there is provided an assemblying screw l4 which extends through the inner peripheral portion 5 of the ring-like member l8 and has screw-threaded engagement with the flange 8. The purpose of the assemblying screw or screws M will be hereinafter brought. out.

Adjacent the outer periphery of the ring-like members 9 and H) a plurality of torque bolts l5, disposed parallel to the axis of sleeve I, extend between and through suitably aligned openings in said members. These bolts are preferably equally spaced from each other circumferentially of the ring-like members 9 and I9 and each of the bolts is provided with a head l6 bearing against the outer face of the ring-like member 9 and preferably rigidly secured thereto by welding. A nut 11 is provided on the opposite end of each of the bolts l5 and engages the radial portion H of the ring-like member ID.

its

Two, annular, ring-like rotatable brake elements or discs l8 and I9 encircling the sleeve I extend into the space between the ring-like members 9 and Ill. The bolts I5 extend through suitable apertures provided in the brake elements l8 and I9, adjacent their inner peripheries, for supporting said elements in concentric relation with said sleeve and for turning same with the car wheel I. a A release bolt 20 is provided parallel to and between each adjacent pair of torque bolts I5. Each of the release bolts 29 comprises a head 2| and a stem made up of cylindrical portions 22 and 23 of different diameters stepped down in the direction away from the head 2|. The head 2| of each bolt 29 is provided for engagement with the outer face of the annular rotatable element l8, and through said element there is provided a. suitable aperture for the cylindrical portion 22 of the bolt to operate, the cylindrical portion 23 of said bolt operating through suitable aligned apertures of smaller diameter provided through the rotatable brake element l9 and the flange ll of the ring-like member ID. A spring seat 24 is mounted over the end of each of the release bolts 28 which projects beyond the outer face of the radial portion ll of the ring-like member l0 and is held thereon by a nut 25, and interposed between said spring seat and the outer I .face of said ring-like member ID is a release spring 26 which is preferably of coil form encircling the bolt.

Each of the release bolts 20 is provided with a shoulder 21 formed at the junction of the two cylindrical portions 22 and 23. The several springs 28 acting on the bolts 20 are provided for pulling the shoulder 21 on the bolts against the rotatable brake element l9 and for then urging said element into engagement with the radial portion ll of the ring-like member II) which defines the position assumed by said brake element when the brakes on the wheel I are released. The head 2| on each of the release bolts 28 is so spaced from the shoulder 21 as to engage and draw the rotatable brake element |8 to its release position with respect to the rotatable element I9 when in its release position. I

A release spring 28 is provided on the cylindrical portion 22 of each of the bolts 28 and acts on the two brake elements I8 and I9 for holding the element 8 against the bolt heads 2| when the brakes are released. The disk-like element 9 is provided with suitable apertures 86 aligned with the release bolt heads 2| through which said heads are adapted to freely move in efiecting an application of the brakes, which will be later described.

The two rotatable brake elements l8 and I9 are interleaved between three, annular non-rotatable brake elements or disks 29, 30 and 3|, the element 29 being disposed closest to the wheel I, the element 38 being disposed between the two rotatable brake elements l8 and I9, while the element 3| is disposed adjacent the outer face of the rotatable element l9. Each of the non-rotatable brake elements 29, 30 and 3| is of the same outside diameter as the rotatable brake elements l8 and I9 while the inside diameter of said nonrotatable elements is somewhat greater than the outside diameters of the ring-like members 9 and I0. Each of the non-rotatable brake elements 30 and 3| is provided with a pair of diametrically oppositely disposed lugs 88 projecting radially from the outer peripheral edge thereof and between said lugs and at both sides thereof there are provided a plurality of similar outstanding lugs 89, the lugs 88 and 89 being preferably equally spaced from each other around the outer peripheral surfaces of said elements. The lugs 88 are of greater circumferential length than the lugs 89 for reasons which will be later apparent. The non-rotatable brake element 29 is provided with a plurality of lugs 89 corresponding in number and disposition to the lugs 88 and 89 on the other two non-rotatable brake elements.

Encircling the sleeve 1 is a support ring 32 lined interiorly with a bearing ring 33 which is journaled on said sleeve. The bearing ring 33 is adapted to bear at its inner end against a shoulder 34 provided on the sleeve 1, while secured to said sleeve and bearing against the outer end of said ring'is an annular member 35 secured to said sleeve by screws 36. The member 35 is provided to act when the brakes are released to hold the support ring 32- and parts of the brake mechanism carried thereby against axial movement relative to the sleeve 1 and'to the parts of the brake mechanism carried by said sleeve which i have been hereinbefore described.

A ring-like disk 31 encircles and is rigidly secured at its inner peripheral edge to the supporting ring 32 preferably by welding. The disk 31 is provided intermediate its edges with an out-'= 50 wardly extending annular ofiset providing in the inner face thereof an annular channel to accommodate the release springs 26 and bolts 20 hereinbefore described. The outer periphery of said disk 31 is substantially the same diameter l as that of the non-rotatable brake elements 29, 38 and 3|, and is' provided at one side with a radially extending lug 18 of such length as to span one of the lugs 88 and a lug 89 at either side thereof on the adjacent non-rotatable element 3|. The disk 31 also has outstanding lugs 9| and 92 aligned with the other lugs 88 and 89, respectively on the non-rotatable brake element 3 I.

An annular ring-like brake cylinder device 65 38 is mounted against the outer face of the ringlike disk 31 in coaxial relation with the rotatable brake elements l8 and I9. The brake cylinder device 38 is provided around its circumference with a plurality of outstanding lugs 39 bear- 70 each of these apertures and screw-threaded into the respective .bores is a bolt 49 having a bed 4| which bears against the-opposite face of k 31 for rigidly securing the brake cylinder devibe to-the disk in coaxial relation with the rotatable brake elements l8 and I9.

Each of the bolts 40 is provided adjacent wheel I with an outstanding portion 42 extending parallel to the axis of the sleeve 1 and provided with three guide portions 43, 44 and 45 of difl'e'rent diameters stepped down in the direction of the car wheel. The guide portions 43 of greatest diameter on the several bolts extend through suitable apertures in the lugs projecting irom the non-rotatable brake element 3| for supporting said element in coaxial relation with the rotatable brake element l9, while the g'uide'portions 44 and 45 extend through suitable apertures in the lugs projecting from the non-rotatable brake elements 39 and 29, respectively, for supporting same also in said relation, the nonrotatable elements 30 and 3| being slidably mounted on the guide sections 44 and 43. The non-rotatable elements 30 and 3| are mounted on the bolts 40 in such a manner that the lugs 88 of the two brake elements are in alignment with each other and with one aligned pair mounted on the center of the three bolts extending through the lug 18 projecting from the disk 31.

The outstanding lugs 88 and39 on the nonrotatable brake element 3| are adapted to engage the heads 4| of the bolts 40 for defining the release position of said element in which position it is spaced from the rotatable brake element |9 when in its release position hereinbefore described. A shoulder 45 formed at the junction of each two guide portions 43 and 44 on the several bolts 49 serves to limit movement of the non-rotatable element 30 in a direction away from the wheel 2 to thereby define its release position in which it is adapted to be spaced midway between the rotatable brake elements 3 and I9 when said rotatable brake elements are in their release position above described. A shoulder 41 formed at the junction of the guide portions' 44 and 45 on each 0! the bolts 40 is adapted to be engaged by the non-rotatable brake element 29 for defining its release position with respect to the rotatable brake element l8 when in its release position. A nut 43 is provided on the end of the outstanding portion 42 of each of the bolts 40 and bears against the non-rotatable element 29 for at all times holding itagainst the shoulder 41 provided on the several bolts. From the above description it'will be evident that the ring-like disk 31 which is journaled on the sleeve I supports the brake cylinder device and the several non-rotatable brake elements through the medium of the bolts 43 in coaxial relation withthe sleeve I and thereby with the wheel I and it will be evident that the rotatable brake elements l9 and I9 are adapted to be free to rotate between the several non-rotatable brake elements when all of said brake elements are in their release positions above described.

The middle of the threebolts 43 extendin through the lug 19 on disk 31 and'the diametri- 40 bears at its inner end against the brake cylinder lug 39 and at its outer end against the cross-head 59 urging said cross-head in a direction away from the brake cylinder device.

The cross-head 53 is provided with two oppositely disposed radially extending arms 52 tothe outer end of each of which is secured one end" of a release bolt 53, the two bolts 53 being disposed one above and one below the bolt 40 and extending parallel therewith. Each of the release bolts 53 extends through suitably aligned through suitably aligned apertures inthe aligned lugs 33 of the non-rotatable brake element 30.

Each of the rods, 53 is provided at the outer end of the enlarged portion 54 with a head 55 for engagement with the lugs 88 of the non-rotatable element 30 for urging said element to its release position, while the inner end of the enlarged portion 54 functions in a like. manner. to engage and urge the non-rotatable element 3| to its release position. f In the drawings, the non-rotatable elements 30 and 3| are shown in their release positions defined by engagement between the lugs 93 on; said elements and, respectively, heads M on the bolts 49 and the shoulders 45 on said bolts, as hereinbefore described.

Anut 55 .is provided on the end of each of the bolts 53 and engages the cross-head 50 whereby the length of said bolts and thereby the force of the release springs 5|v may be adjusted to insure movement of the non-rotatable brake elements 30 and 3| to their release positions just described. It will be noted that only the nonrotatable elements 30 and 3| are connected to the release bolts 53 and are capable of axial movement, since the non-rotatable element 29 is secured against such movement between thepacking cup 5| between which and the piston head there are provided a pair of' lubricating rings 52 engaging both the inner and outer walls of the piston chamber, said rings being made of any suitable lubricant absorbing and spreading material, such as felt.

The packing cup 5| is open at the face opposite the piston head 59 to a pressure chamber 53 which is connected to a pipe 54 through which fluid under pressure is adapted to be supplied to and released irom said'chamber or controlling the braking operation of. said iston. At the opposite side of the piston head 59 there is provided a non-pressure chamber 55 which is open to the atmosphere in any desired manner such as through apertures 55 provided in the disk 31 and thence through the space between said disk and the adjacent non-rotatable brake element The brake cylinder piston 59 is provided with aplurality of piston pins 53 equally spaced from eachother; and freely extending through the apertures 66, which are suitably aligned, into engagement with the adjacent face of the nonrotatable element 3| at points substantially midway between the overlapping portions of the non-rotatable and rotatable brake elements These pins are of such length as to provide for engagement between thenon-rotatable element 3| and the several nuts 4I upon substantial engagement between the packing cup BI and the closed end of chamber 51.

A flat insulating ring 81 is interposed in the space between the non-rotatable brake element 3| and the disk 31. The inside and outside diameters of this insulating ring'are substantially the same as of the brake cylinder device and it is provided with a plurality of spaced apertures through which the piston pins 58' extend for supporting thering. As most clearly shown in Fig. 6, each of the piston pins 58 is provided on the brake cylinder side of the insulating ring 61 with a shoulder 88 for engagement by the ring, while at the opposite side said ring is engaged by a snap ring 69 disposed in an annular groove provided adjacent the end of each piston pin. The insulating ring 61 is thus secured in a position in which it is spaced from both the nonrotatable brake element 3| and the disk 31 and is adapted to move with the piston pins 58, as will be evident.

The ring 61 is preferably provided on the face adjacent the non-rotatable brake element 3| with a highly polished surface adapted to reflect heat back toward said element and thus away from the brake cylinder piston 59. The ring is also made of a material such as copper or an alloy thereof which has the property of quickly giving up absorbed heat for reasons which will be later brought out.

The rotatable brake elements I8 and I9 are provided in both of their opposite braking faces with a plurality of radially arranged slots 12, the slots in'one face of the elements being staggered with respect to those in the opposite face. These slots open through the outer peripheral edges of the rotatable brake elements directly to the atmosphere, while the inner ends of the slots in the rotatable brake element I8 and in the adjacent face of the rotatable brake element I8 open past the inner peripheral edges of the non-rotatable brake elements 29 and 30 to a chamber I3. This chamber is formed between the disk: like members 9 and I and is open to the atmosphere through a plurality of apertures I4 provided in the cylindrical portion I2 of member I8 and which open to a chamber I formed between the element I8 and disk 31, the chamber I5 being in turn open to the atmosphere through a plurality of apertures 16 in the disk 31. The radial slots 12 provided in the outer face of the rotatable brake element I8 are open at their inner ends to the chamber I5.

The apertures I6 are so arranged that upon rotary movement of the disk 31 relative to the sleeve 1 said apertures will line up with the torque screws I3 to permit said screws to be applied in or removed from the positions in which they are shown in the drawings.

A torque plate 19 is rigidly secured to the lug I8 projecting from disk 31 by a plurality of rivets 80. This plate is provided at its outer end with two bosses 8I which are spaced from each other and each of which is provided with a vertically arranged bore in axial alignment with a corresponding bore in the other. A torque arm 82 is provided having two spaced cylindrical guide portions 83 disposed between and substantially engaging the adjacent faces of the bosses8l and having aligned bores provided in coaxial relation with those in the bosses 8I. A vertically arranged torque pin 84 is provided which extends through the bosses 8I and the bores in the torque arm 82 thereby rigidly securing the disk element 3'1, brake cylinder device and the several nonrotatable brake elements against rotation relative to the torque arm 82. The torque arm 82 is rigidly connected to a bar 85 which is adapted to be connected, in any desired manner and to any suitable portion of the vehicle truck (not shown) for holding the torque arm 82, the pin 84 and thereby the disk 31, brake cylinder device and several non-rotatable elements against rotation with the car wheel I.

Assembling of the brake mechanism The brake mechanism, exclusive of the torque arm 82, is adapted to be assembled into a unit at a bench in a shop remote from the vehicle to which it is to be applied and then, when desired, applied as a unit to the wheel of the vehicle, following which the torque arm 85 may be connected to the vehicle truck and to the brake mechanism as shown in the drawings.

The assembling of the brake mechanism is accomplished in the following manner, the various parts hereinbefore described as being welded together being previously secured in their proper working relation.

The rotatable brake elements I8 and I9 with the non-rotatable brake element 38 interposed therebetween are first slipped over the torque bolts I5. Next the small release springs 28 are interposed between the rotatable brake elements and the release bolts 20 are slipped into place for 4 holding said springs in position. Then the disklike member I0 is applied over the outer ends of the bolts I5 following which the assembling screws I 4 are applied to rigidly secure said memher to the flange 8 of sleeve 1. The release springs 26, spring seats 24 and nuts 25 are next applied to the release bolts 28 and said nuts adjusted to provide the desired compression of said springs for insuring release movement of the rotatable brake elements I8 and I9.

The several bolts 40 are next inserted through the apertures in the lugs projecting from the support disk 31 and screwed into the lugs 39 projecting from the brake cylinder device securing said device to said disk. The brake cylin der piston 58, having mounted thereon the packing cup 6| and being provided with the piston pins 58, is mounted in place in the brake cylinder device before said device is secured to the disc 31, and at the time of securing, the piston pins 58 will be lined up for extending through the apertures 86 in said disk, as will be evident.

After the brake cylinder device is secured to the disk 31, the non-rotatable brake element 3| is slipped on to the guide sections 43 of the several bolts 40 following which this assembly of parts, including the disk-like member 31, is slipped on to the bearing on the sleeve 1, and during such movement the apertures in the lugs on the nonrotatable element 30 are lined up to receive the cylindrical guide portions 44 of the several bolts 48. After .the disk-like member 31 is slipped onto the sleeve 31 to its working position, the non-rotatable brake element 29 is slipped over the guide sections 45 of the several bolts 40 and then the nuts 48 are applied to the ends of said 1 bolts for securing the non-rotatable element 29 against the shoulders 41. The ring 35 is next slipped over the end of the sleeve 1 and secured in place by the screws 36.

The release springs the extensions 49 of the bolts 49 following which the release rods 53 are threaded from outside of the non-rotatable brake element 39 through the apertures in the lugs thereof and through those in the lugs of the non-rotatable element 3|. The cross-heads 59 are then slipped over the extensions 49 of'bolts' 49 against the pressure of springs 5| and the bolts 53 are threaded through the ends of said cross-heads. The nuts 56 are then applied to the ends of the bolts 53 and adjusted to provide the desired compression of springs 5| for insuring release movement of the non-rotatable brake elements 39 and 3|.

All of the various parts of the brake mechanism except the torque arm 82 are now assembled into a unit in their proper working relation, and as such a unit said mechanism is adapted to be mounted on or removed from the wheel I of avehicle.

In order to apply the brake mechanism to the wheel, said mechanism is mounted against the wheel hub 3 following which the torque bolts. l3 are inserted through the apertures 19 in disk 31, and thence through the aligned apertures extending through the members 9 and I9 and flange 8 of the sleeve 1. A wrench (not shown) is then inserted through the apertures 19 and connected with the head of the torque screws l3 following which said screws are lined up and screwed into the openings provided in the end I of the wheel hub '2, wherebythesleeve I, members 9 and I9 and the rotatable brake element l8 and I9 are'rigidly secured to the wheel" for rotation therewith. After the brake mechanism is applied to the wheel, as just described, the assembllng screws |4 serve no further useful purpose, the only purpose of these screws being to hold certain parts of the mechanism in an assembled condition prior to application to the car wheel. The assembling screws may however be left in place after the brake mechanism is applied to the wheel if such is desired.

After the brake mechanism is applied to the wheel I the torque bar 85 is connected to the disk 31 of said mechanism by the vertically arranged bolt 84 and suitably connected to any desired part of the vehicle truck for securing said disk and parts of the brake mechanism carried thereby against rotation with the wheel I.

Operation of theprake mechanism With a brake mechanism applied to the 'wheel l as above described, if it is desired to brake said wheel, fluid under pressure is supplied through the pipe 64 to the pressure chamber 63 wherein it acts on the brake cylinder piston 59 to effect movement thereof in the direction of said wheel.

As the brake cylinder piston 59 is thus operated it acts through the piston pins 58 to shift the non-rotatable brake element 3| along the guide portions 43 of bolts-49 into engagement with the rotatable brake element l9. Upon such engagement the rotatable brake element I9 is picked up and moved along the torque bolts |5 into engagement with the non-rotatablelbrake element 39 which is then picked up and moved along the guide portions 44 of the bolts 49 into contact with the rotatable brake element l8.

As the rotatable brake element I9 is moved along the torque bolts l5 as just described, it acts through shoulders 2'! to carrythe release bolts 29 along, due to which the springs 28 act to shift 5| are next slipped. .over

the rotatable brake element l8 in the direction of the non-rotatable brake element 29. As a result, the rotatable brake element I8 is moved into contact with the non-rotatable element 29 at about the same time that the rotatable element 5 l9 engages the non-rotatable element 39, after which the continued movement of the rotatable element l9 to effect engagement between the non-rotatable element 39 and rotatable element I8 is relative to the rotatable element |8 and op- 10 posed by the springs 28 which are compressed.

During this relative movement, the heads 2| of bolts 29 are free to move through apertures 89 in the disk member 9, as will be apparent.

After the several brake elements are thus moved into frictional interengagement the pressure of fluid acting on the brake. cylinder piston 59 tends to force said elements in the direction of the wheel I, while the reaction of the pressure of fluid acting on the brake cylinder piston is transmitted through the brake cylinder device, to

bolts 49 and thence to the non-rotatable brake element 29 tending to move same in the direction away from the wheel. The rotatable brake elements l8 and I9 and the non-rotatable brake elements 39 and 3|. are thus subjected to the squeezing action of opposing pressures applied through the non-rotatable brake element 29 and the brake cylinder piston 59. As a result of this action the several non-rotatable brake elements 39 create a drag on the rotatable brake elements I8 and I9 thereby effecting braking of said rotatable elements which is in turn transmitted through the disk-like members 9 and I9 and torque bolts l3 to the car wheel I for efiecting braking of said wheel..

The degree with which the rotatable brake elements l8 and I9 and thereby the wheel I arebraked, as just described, depends upon the pressure of fluid supplied to chamber 63 to act on 40 the brake cylinder piston 59 and to react through the brake cylinder device 38 and bolts 49 on the non-rotatable brake element 29, and this pressure may be varied in any conventional manner to provide any desired degree of braking of wheel 5 I, as will be apparent.. l

As the several annular friction brake elements are moved into frictional interengagement as just described, it will be noted that the release springs 5| oppose such movement of the non- 5o rotatable elements '39 and 3|, and the release springs 29 oppose such movement of the rotatable brake elements l9 and I8, while movement of the rotatable element IE! to effect engagement between the non-rotatable brake element 39 and the rotatable brake element I8 is also opposed by the springs 22.

During braking it will be evident that the nonrotatable brake-elements and the brake cylinder device are held against rotation with the ro- 0 tatable brake elements due to the action of the torque rod 85.

When the several non-rotatable brake elements are forced into frictional braking engagement with the rotatable brake elements, all of the 5 brake elements become heated due to this frictional contact. The slots 12 provided in the opposite faces of the rotatable brake elements act however during braking to draw air from chambers I3 and 15 and force same over the contact- 79 ing surfaces of the several elements and through the outer ends of said slots to the atmosphere. This flow of air over the braking facesof the brake elements is provided. for absorbing heat f om said elements and dissipating'it to the atmosphere so as to avoid excessive or destructive heating of the elements and to thereby maintain the temperature of the elements at a sufliciently low degree to provide eilicient braking.

The polished surface of the insulating ring 61 is also effective at this time to reflect the heat radiated from the brake elements away from the brake cylinder device so as to protect the lubricant and the packing cup 6| in said device. When the wheel I is rolling along the rail 2 there will be a natural flow of air currents over the opposite faces of the insulating ring 61 and these .air currents are adapted to carry heat away from the insulating ring so as to thereby further insulate the brake cylinder device and parts thereof from heat created in the brake elements during braking. Since the insulating ring is made from a material such as copper which has the properties of quickly absorbing and quickly giving up heat it will be evident that it will act as an effective barrier against the transfer of heat to the brake cylinder device, so that the brake cylinder device will be capable of operation over a long period of time.

When it is desired to effect a release of the brakes after an application, the fluid under pressure is ventedfrom the brake cylinder piston chamber 63 through the brake cylinder pipe 64 thereby relieving the force on the brake cylinder piston 59 and the reacting force on the non-rotatable brake element 29. As a result, the release springs 5l acting through the rods 53 effect movement of said rods in the direction away from the wheel, while the release springs 26 acting on the release bolts 20 effect movement of said bolts in the same direction.

As the rods 53 are thus operated they act' through the shoulders engaging the lugs projecting from the non-rotatable element 3| to move said element against the nuts .II, and through the heads 5| on the ends of said rods to move the non-rotatable element 30 into engagement with the shoulders 46 provided on the bolts 40, the nuts 4| and shoulders 46 defining the release positions of said elements as hereinbefore described.

As the release bolts 20 are returned to their release positions by springs 26 the shoulders 21 on said bolts return the rotatable brake element l9 into engagement with the disk-like member Ill, and after a certain release movement of said bolts, the heads 2| thereof engage the rotatable brake element l8 and effect movement thereof to its release position, the springs 22 provided on said bolts between the rotatable brake elements ensuring that the rotatable brake element l8 will be maintained in contact with the heads 2| of the release bolts after this release operation. With the several brake elements moved to their releasepositions, as just described, the rotatable brake elements l8 and H are spaced from and therefore out of contact with the non-rotatable brake elements and thus free to rotate with the wheel I.

It will be noted that the brake cylinder piston 59 is moved to its release position by movement of the non-rotatable brake element 3| to its release position. A brake cylinder piston of this type often has a relatively high resistance to movement, but the release movement of said piston and thereby of rotatable brake element 3| is ensured by the location of the release springs 5| outside or at one end of the pile of brake elements which provides for the use of relatively large springs, if necessary, to accomplish this end,

It will also be noted that the release springs 26 for effecting release movement of the rotatable brake elements I 8 and I9 are disposed at the outer face of the element l9 so that their design is not confined to the space existing between the elements, as in conventional practice, but rather such springs may be of such size as required to ensure the proper release movement of the rotatable brake elements 18 and I9. v

The only function of the springs 22 interposed between the rotatable brake elements l8 and i9 is to ensure that the rotatable element l8 will be held against the heads 2i on the release bolts 20 when 'the brakes are released "so as to avoid axial movement of the rotatable element l8 into dragging contact with the non-rotatable brake- The ring 35 engaging the bearing 33 acts when the brakes are released to hold the disk-like member 31 and thereby the non-rotatable brake elements 29, 30 and 3| against axial movement relative to the rotatable brake elements l8 and I9 so that when the brakes are released the nonrotatable brake elements will be held in their release positions above described out of contact with the rotatable brake elements l8 and I9, thereby avoiding, as will be evident, a dragging contact between said elements. When the brakes on the wheel I are applied as above described it will be evident that the ring 35 serves no useful purpose and it will be further evident that the disk member 31 which carries the brake cylinder device is not subject to any of the forces incident to braking. This disk 3! acts merely as a support for the non-rotatable brake elements and brake cylinder device when the brakes are applied, the same as when the brakes are released, since the force applied to the brake cylinder piston 59 and the reaction thereof are taken wholly by the disk brake elements.

Summary From the above description it will be evident that the novel brake mechanism is relatively simple and compact in construction. Its design is such as to ensure positive and efilcient operation of the various parts. The design also provides for most eflicient fitting and assembling of parts since the mechanism can be assembled as a complete unit in railway shops or the like at a point remote from where it may. be applied to the wheel of a vehicle. Not only the initial assembling of the mechanism but repairing thereof can thus be effected at locations providing adequate facilities and competent workmen. The application of such units to the wheels of vehicles can thus be effected by relatively unskilled workmen and by the simplest of tools. By this arrangement relatively long life and most efficient braking operation of the brake mechanism is ensured.

While one illustrative embodiment of the invention has been described in detail it is not the intention to limit its scope to that embodiment or otherwise than by the terms of the appended claims.

Having now described our invention, what we clabim as new and desire to secure by Letters Paten is:

l. A disk brake mechanism for a railway vehicle wheel comprising a pile of two annular roiambic friction brake elements secured to -roaaiaeie tate with said wheel and an annular non-rotatable friction brake element interposed between said rotatable brake elements, actuating means operative to effect frictional interengagement between said rotatable and non rotatable brake elements to effect braking of said wheel, release means operative upon release of said actuating means to effect disengagement of said elements from each other, the release means for said rotatablebrake elements including at least one spring dis osed beyond-one end of said pile of elements, and means operatively connecting said spring to both of said rotatable brake elements.

2. A disk brake mechanism for a wheel of a railway vehicle comprising a pile of two annular rotatable friction brake elements secured to rotate with said wheel and an annular non-rotatable friction brake element interposed between said rotatable elements in coaxial relation therewith, actuating means operative to efi'ect frictional braking interengagement between said elements, release means operative upon release of said actuating means for effecting disengagement of said elements from each other,'the release means for said rotatable elements comprising at least one spring disposed beyond the outside face of one of said rotatable elements, and means operatively connecting said spring to both of said rotatable elements.

3. A disk brake mechanism for a wheel of a railway vehicle comprising a plurality of annular rotatable friction brake elements secured to rotate with said wheel, a plurality of annular nonrotatable friction braking elements interleaved with said rotatable elements, actuating means operative to move said elements axially into frictional interengagement to effect braking of said wheel, release means operative upon the release of said actuating means for effecting movement of said elements out of engagement with each other, the release means for said rotatable elements comprising at least one spring disposed beyond the outside face of one of the outer-most of said rotatableelements, and .means operatively connecting said spring to all of said rotatable elements. I

4. A disk brake mechanism for a wheel of a railway vehicle comprising a plurality of annular rotatable friction brake elements secured to rotate with said wheel, a plurality of annular non-rotatable friction .braking elements interleaved with said rotatable elements, actuating means operative to move said elements axially into frictional interengagement to effect braking of said wheel, release means operative upon the release of said actuating means for effecting tatable elements comprising at least one spring disposed beyond the outside face of one of the outer-most of said non-rotatable brake elements, and operatively connected to all of said nonrotatable elements.

5'. A disk brake mechanism for a railway vehicle wheel comprising a rigid structure secured to rotate with said wheel, a structure journaled 4 on said-rigid structure, a plurality of interleaved annular rotatable and non-rotatable friction brake elements having release positions spaced from each other and being movable'axially into frictional interengagement to efiect braking of said wheel, said rotatable elements being secured to said rigid structure for rotation'with said wheel, the journaled structure extending past the outer face of one of the outer-most of said rotatable elements and carrying said non-rotatable elements, and release means for effecting movement of said brake elements out of interengagement to said release positions, the release means for said rotatable elements includi spring means disposed between said journaled structure and the adjacent rotatable element and operatively connected to both of said rotatable elements, and the release means for said nonrotatable elements including spring means carried by said joumaled structure beyond the outer face of one of the outer-most of the non-rotatable brake elements and operatively connected to said non-rotatable elements. I

v 6. A disk brake mechanism for a wheel of a railway vehicle truck comprising a rigid structure secured to rotate with said wheel, a pair of annular rotatable friction brake elements encircling and carried by said structure and capable of axial movement relative thereto, said elements having-brake release positions with respect to said structure, the release position of one of said elements being defined by engagement thereof with said structure, release means for said rotatable elements movable with one of said rotatable elements and relative to the other rotatable elements in one direction and operative upon movement, in the opposite direction to effect movement of said elements to brake release positions in which they are spaced apart a predetermined distance, spring means for actuating said release means, resilient means acting on said other rotatable element for holding same against movement out of its release position relative to said release means, a pair of annular non-rotatable friction brake elements one disposed between said rotatable brake elements and the other disposed adjacent the opposite face of one of said rotatable brake elements, actuating means for effecting movement of said rotatable brake elements and of the non-rotatable'brake element interposed between in the direction of the other non-rotatable brake element foreffecting frictional interengagement between said elements to brake said wheel, said spring means opposing movement of said rotatable brake elements into interengagement with said nonrotatable elements and being operative upon the release of said actuating means to effect movement of said rotatable elements to said release positions, and spring means acting on the nonrotatable element disposed between said rotatable elements to effect movement thereof to a release position midway between said rotatable elements.

7. A disk brake mechanism for a railway vehicle wheel comprising a rigid structure secured I to rotate with said wheel, a structure journaled on said rigid structure, a plurality of interleaved annular rotatable and non-rotatable frictionwheel, the journaled structure extending past the outer face of one of the outer-most of said rotatable elements and carrying said non-rotatable elements, and release means for effecting movement of said brake elements out of in-- lease means for said rotatable elements including spring means disposed between said journaled structure and the adjacent rotatable element and operatively connected to both of said rotatable elements, and the release means for said nonrotatable elements including spring means carried by said journaled structure beyond the outer face of one of the outer-most of the non-rotatable brake elements and operatively connected to said non-rotatable elements, both of said spring means being disposed beyond the outer face of the outer-most of the respective brake elements to whiclrthey are connected.

8. A disk brake mechanism for a wheel of a railway vehicle truck comprising a rigid structure secured to rotate with said wheel, a pair of annular rotatable friction brake elements encircling and carried by said structure and capable of axial movement relative thereto, said elements having brake release positions with respect to said structure, the release position of one of said elementsbeing defined by engagement thereof with said structure, a plurality of release bolts carried by said structure and provided with shoulders for engaging said one rotatable element for effecting movement thereof against said structure, each of said bolts having another shoulder spaced from the first named shoulder and arranged to engage the other of said rotatable elements for effecting movement thereof to its release position, spring means disposed beyond the outside face of one of said rotatable elements and acting on each of said release bolts for operating same to move said brake elements to their release positions, a pair of annular non-rotatable friction brake elements one disposed between said rotatable brake elements and the other disposed adjacent the outside face of one of said rotatable brake elements, means for effecting movement of said rotatable brake elements and of the non-rotatable brake element interposed between in the direction of the other non-rotatable brake element for effecting frictional interengagement between said elements to brake said wheel, said spring means being operative upon the release of said actuating means for returning said rotatable brake elements to their release positions, and means acting on the non-rotatable brake element disposed between said two rotatable brake elements for centralizing same between said two rotatable brake elements.

9. A disk brake mechanism for a wheel of a railway vehicle comprising a rigid structure secured to rotate with said wheel, a plurality of axially movable, annular rotatable friction brake elements secured to said structure for rotation with said wheel, a plurality of annular non-rotatable friction brake elements interleaved with said rotatable friction brake elements, actuating ,means journaled on and carried by said rigid upon release of said actuating means, and spring 2,218,816 'terengagement to said release positions, the reof engagement with said rotatable elements upon release of said actuating means.

10. A disk brake mechanism for a. wheel of a railway vehicle comprising a rigid structure secured to rotate with said wheel, an annular rotatable friction brake element secured to said structure for rotation with said wheel, an an-.

nular non-rotatable friction brake element disposed at each of the opposite sides of said rotatable brake element in coaxial relation therewith, a structure journaled on said rigid strucsaid non-rotatable elements, and means connecting said casing to the other of said non-rotatable elements cooperative with said piston upon operation thereof to eifect frictional interengagement between said elements for braking said wheel.

11. A disk brake mechanism for a wheel of a railway v'ehicle comprising a rigid structure secured to rotate with said wheel, an annular rotatable friction brake element secured to said structure for rotation with said wheel, an annular non-rotatable friction brake element disposed at each of the opposite sides of said rotatable brake element in coaxial relation there with, a member journaled on and supported by said rigid structure and secured against rotation, an annular ring-like brake cylinder device comprising a casing and a fluid operative piston therein operatively connected to one of said non-rotatable elements, and means securing said casing to said member and to the other of said non-rotatable elements whereby said casing is cooperative with said piston to effect frictional braking interengagement between said elements upon operation of said piston.

12. A disk brake mechanism for a wheel of a railway vehicle comprising a rigid structure secured to rotate with said wheel, a plurality of annular rotatable and axially movable friction brake elements secured to said structure for rotation therewith, a plurality of annular non-rotatable friction brake elements interleaved with said rotatable elements, each of said rotatable and non-rotatable brake elements having a release position disengaged from the brake elements at either side thereof, a structure journaled on and carried by said rigid structure and secured against rotation and carrying said nonrotatable elements, brake cylinder means carriedby the journaled structure operative to actuate said rotatable and non-rotatable braking elements into frictional interengagement to effect braking of said wheel, a plurality of springs carried by said rigid structure beyond the outer face of one of the outer-most of the rotatable brake elements operatively connected to said rotat able brake elements for effecting movement thereof to their release positions upon release of said brake cylinder means, and spring means carried by said journaled structure beyond the outer face of one of the outer-most of the non-rotatable elements and operatively connected to said non-rotatable elements for effecting movement thereof to their release positions upon release of said brake cylinder means.

13. A disk brake mechanism for a wheel of a railway vehicle comprising a rigid structure secured to rotate with said wheel, an annular rotatable friction brake element secured to said structure for rotation with said wheel, an annular non-rotatable friction brake element disposed adjacent each of the opposite faces of said rotatable brake element, said non-rotatable elemerits having release positions spaced from said faces, a structure journaled on said rigid structuating means carried by the journaled' structure and connected directly to both of said non-rotatable elements for applying forces thereto in the direction of said rotatable element forefiecting frictional braking interengagement of said elements to brake said wheel, means operative upon the release of said actuating means to position said non-rotatable brake .elements in their release positions, and means securing said jour naled means against axial movement relative to said. rigid structure for maintaining said non-rotatable elements disengaged from said rotatable element when said non-rotatable brake elements are in their release positions.

14. A disk brake mechanism for a wheel of a railway vehicle comprisinga rigid structure se- -'cured to'rotate with said wheel, a pair of annular rotatable friction brake. elements encircling said structure, means carried by said structure securing said elements for rotation and operatively connected to one of the outermost non-.rotatable elements, means securing the other outer-most non-rotatable element against movement relative to said support members, said brake cylinder device being operative throughthe one non-rotatable element and said means for effecting frictionalbraking' interengagement between said non-rotatable elements and said rotatable elements, and spring means acting on said rotatable elements and on said non-rotatable elements operative upon the release of said actuating means for effecting disengagement of said elements from each other.

15. A disk brake mechanism for a wheel of a railway vehicle comprising a rigid structure secured to rotate'with said wheel, an annular rotatable friction brake element secured to rotate with said structure, a disk-like member journaled on and carried by said rigid structure and secured against rotation, an annular non-rotatable friction brake element interposed between said rotatable brake element and the adjacent face of said member and carried by said member in coaxial relation with said rotatable element, and an annular brake cylinder device mounted on the opposite face of said member in coaxial relation with said brake element, said brake cylinder device comprising a casing secured to-said member and having an annular chamber open at the end adjacent said member, said member closing the open end of said chamber, abrake cylinder piston mounted in said chamber, and a plurality of actuating pins extending through apertures in said member operatively connecting said piston to said non-ro tatable element for effecting movementof said non-rotatable element into frictional interen-r gagement with said rotatable brake element for braking said wheel.

. JOSEPH C. McCUNE. GEORGE K. NEWEIL. 

